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<P><B><A NAME=2.1>2.1. Supported formats</A></B></P>
<P><B>MPlayer</B> can read/play from the following devices/formats:<BR>
<UL>
<LI> <A HREF="#2.1.1.1">VCD</A> (Video CD) directly from CD-ROM or from CDRwin's .bin image file
<LI> <A HREF="#2.1.1.1">DVD</A>, directly from your DVD disk, using libdvdread for decryption
<LI> <A HREF="#2.1.1.1">MPEG 1/2</A> System Stream (PS/PES/VOB) and Elementary Stream (ES) file
formats
<LI> <A HREF="#2.1.1.2">RIFF AVI</A> file format
<LI> <A HREF="#2.1.1.3">ASF/WMV</A> 1.0 file format
<LI> <A HREF="#2.1.1.4">QT/MOV</A> file format with (un)compressed headers
<LI> <A HREF="#2.1.1.5">VIVO</A> format (.viv files)
<LI> supports <A HREF="documentation.html#3.3">reading from stdin</A>, or network via HTTP
</UL></P>
<P>Note: about realmedia (.ra/.rm) support read the FAQ!</P>
<P>It's important to clarify a popular mistake. When people see a file with
<B>.AVI</B> extension, they instantly declare that isn't an MPEG file.
That's not true. At least not entirely. If you tell them that such a file
can contain MPEG1 video, they laugh at you. Feel free to kick their dumbass
faces, then tell them to RTFM.</P>
<P>You see, a <B>codec</B> isn't equal to a <B>file format</B>.<BR>
Video <B>codecs</B> are: MPEG1, MPEG2, DivX, Indeo5, 3ivx.<BR>
Video <B>formats</B> are: MPG, AVI, ASF.<BR>
</P>
<P>In theory, you can happily put an OpenDivX video and MP3 audio
into a <B>.MPG</B> format file. Though most players won't play it, since
they expect MPEG1 video and MP2 audio (<B>.MPG</B> doesn't have the
necessary fields to describe its video and audio streams, like <B>.AVI</B>
does). Or put MPEG1 video to an .AVI. For example <A HREF="http://ffmpeg.sourceforge.net">ffmpeg</A> can
create these files.</P>
<P>Audio <B>codecs</B> and <B>formats</B> are basically the same terms.</P>
<P><B><A NAME=2.1.1>2.1.1. Video formats</A></B></P>
<P><B><A NAME=2.1.1.1>2.1.1.1. MPEG files</A></B></P>
<P>
<LI>MPG : this is the most <B>basic</B> form of MPEG file formats. Contains
MPEG1 video, and MP2 (MPEG-1 layer 2) audio, or rarely MP1.</LI>
<LI>DAT : this is the very same format as MPG, just different extension. Used
on <B>Video CD</B>s. Due to the nature VCDs are created and Linux is designed,
the DAT files can't be played nor copied from VCDs. You have to use the
<CODE>-vcd</CODE> option to play the VideoCD.</LI>
<LI>VOB : this is the MPEG file format on <B>DVD</B>s. The same as MPG, plus
capability to contain subtitles, or non-MPEG (AC3) audio. Contains encoded MPEG2
video, and usually AC3 audio, but MP2 is allowed too.<BR>
<B>Read the <A HREF="cd-dvd.html#4.2">DVD section</A> !</B></LI>
</P>
<P>In MPEG files, series of frames are grouped together, and are independent
from the other groups. What this means is you can cut/join an MPEG file with
standard file-tools (like dd, cut), and it remains completely functional.</P>
<P>One important feature for MPGs is that they have a field to describe
the aspect ratio of the video stream within. For example SVCDs have
480x480 resolution video, and in the header that field is set to 4:3, so
it's played at 640x480. AVI files don't have this field, so one has to
rescale it during encoding.</P>
<P><B><A NAME=2.1.1.2>2.1.1.2. AVI files</A></B></P>
<P>Designed by Micro$oft, the <B>AVI (Audio Video Interleaved)</B> is a
widespread multipurpose format, currently used mostly for DivX and DivX4
videos. Has many known drawbacks, and inabilities (for example in streaming).
Has support for one video stream, and 99 audio streams. Can be as big as
2Gb. There exists an extension for it to be bigger, called <B>OpenDMS</B>.
M$ currently strongly discourages its use and propagates ASF/WMV. Not if
anybody cares.<BR>
<B>NOTE</B> : DV cameras can create two types of AVI format, one is the usual and
playable, the other is neither.</P>
<P>There are two kinds of AVI files:
<UL>
<LI><B>Interleaved</B> : audio and video content is interleaved. This is the
standard usage. Recommended and mostly used. Some tools create interleaved
AVIs with bad sync. <B>MPlayer</B> detects these as interleaved, and this
climaxes in loss of A/V sync, probably at seeking. These files should be
played as non-interleaved (with the <CODE>-ni</CODE> option).</LI>
<LI><B>Non-interleaved</B> : bad. First come the whole video stream, then the whole
audio stream, thus needs a lot of seeking. It's very bad when playing from
network or CDROM.</LI>
</UL>
</P>
<P>MPlayer supports 2 kind of timing for AVI files:
<UL>
<LI><B>bps-based</B> : it is based on bitrate/samplerate of video/audio stream. This
method is used by most players, including avifile and windows media player.
Files with broken headers, and files created with VBR audio but not
VBR-compliant encoder will result in A/V desync with this method (mostly at
seeking).</LI>
<LI><B>interleaving-based</B> : it doesn't use bitrate value of the header, instead
it uses the relative position of interleaved audio and video chunks. Makes
some badly encoded file with VBR audio playable.</LI>
</UL>
</P>
<P>Any audio and video codec is allowed, but note that VBR audio isn't well
supported by most of the players. The file format makes it possible to use VBR
audio, but most players expect CBR audio, thus they fail with VBR. VBR is
unusual, and Microsoft's AVI specs only describe CBR audio. I also note, that
most AVI encoders/multiplexers create bad files if using VBR audio. Only 2
exception (known by me): NaNDub and <A HREF="encoding.html">MEncoder</A>.</P>
<P><B><A NAME=2.1.1.3>2.1.1.3. ASF/WMV files</A></B></P>
<P>ASF (active streaming format) comes from Microsoft. They developed two
variants of ASF, v1.0 and v2.0. v1.0 is used by their media tools (windows
media player and windows media encoder) and is very secret. v2.0 is published
and patented :). Of course they differ, there is no compatibility at all (it's
just another legal game). <B>MPlayer</B> supports only v1.0, as nobody has ever seen
v2.0 files :) . Note, that .ASF files nowdays come with the extension .WMA or
.WMV.</P>
<P><B><A NAME=2.1.1.4>2.1.1.4. QuickTime/MOV files</A></B></P>
<P>These are from Macintosh. Usually have extensions of .QT or .MOV . Note
that since the MPEG4 Group chose QuickTime as the recommended file format
for MPEG4, their .MOV files come with .MPG or .MP4 extension (interesting
that in these files the video stream is a real .MPG file. With the
<CODE>-dumpvideo</CODE> option you can even extract it.).</P>
<P><B>Codecs</B>: any codecs allowed, both CBR and VBR. Note: most new mov files use
<B>Sorenson</B> video and QDesign Music audio. These formats are completely
secret, and only Apple's quicktime player is able to play these files (on
win/mac only).</P>
<P><B><A NAME=2.1.1.5>2.1.1.5. VIV files</A></B></P>
<P><B>MPlayer</B> happily demuxes VIVO file formats. The format's big
disadvantage is that it has no index block, nor fixed packetsize or sync bytes,
and most files lack even keyframes, so forget seeking!</P>
<P>VIVO/1.0 files' video codec is standard <B>h.263</B> . The VIVO/2.0 files'
video codec is a modified, nonstandard <B>h.263</B> . Audio is the same,
it may be <B>g.723</B> (standard), or <B>Vivo Siren</B> .</P>
<P>See the <A HREF=codecs.html#2.2.1.4>VIVO video codec</A>
and <A HREF=codecs.html#2.2.2.4>VIVO audio codec</A> sections for installation
instructions.</P>
<P><B><A NAME=2.1.2>2.1.2. Audio formats</A></B></P>
<P>Currently <B>MPlayer</B> is still a <B>Movie</B> and not a <B>Media</B>
player, thus the pure audio formats (for example MP3, WAV, audio ASF) are
unplayable. Use <A HREF="http://www.xmms.org">xmms</A>, <A HREF="http://www.mpg123.de">mpg123</A>
or whatever.</P>
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